1. Field of the Invention
This invention relates generally to backpacks, and is concerned in particular with an internal injection molded partial-perimeter frame for insertion in backpacks formed principally of fabric.
2. Description of Related Art
Although the frame of the present invention is useful in a wide range of applications, its design is particularly suited for use in backpacks of military combat personnel.
Soldiers engaged in combat must be able to carry gear while wearing bulky body armor vests and water reservoirs (commonly known as Camelbacks or hydration reservoirs). The preferred location for these items is on the wearer's back. The difficulty is that soldiers often need to carry additional gear (such as ammunition, radios, batteries, etc.) into battle as well. The preferred location for this gear is in a back-worn pack which conflicts with their armor vest and/or hydration reservoir.
Prior art backpacks used for this purpose are typically one of two types: an all-fabric design that uses only its basic shape and support straps to stabilize and support the load; and, a plastic sheet design which adds a panel sewn or inserted into a pocket in the pack's wall adjacent to the wearer's back to protect the wearer from the pack's contents and to provide some additional support for the load. These designs do not adequately support the oft considerable weight carried in this fashion, and they do not stabilize these loads adequately during the rigors of combat.
The loads primarily carried, ammunition and the like, are very dense. Even a relatively small payload volume presents serious challenges to wearer comfort and balance. Loads will sag, thus concentrating pressure uncomfortably.
Additionally, the wearer's body armor back plate creates a convex surface on which prior art backpacks slide around. While running, climbing, crawling, etc., the load will tend to shift, thus compromising balance during critical moments. This problem is exacerbated when a hydration reservoir is worn on top of the armor plate and under the backpack.
The layering of body armor, hydration reservoir, and backpack also shifts the center of gravity of the carried load rearward, causing the wearer to bend more at the waist to maintain balance. This carriage position is inefficient and uncomfortable. Prior art backpacks that use support sheets or full-frame support systems are even more prone to this than fabric/strap designs. The rigid sheet, frame members, etc., tend to ride on the highest point on the back (in this application on the armor plate or hydration reservoir). This forces the backpack away from the wearer's center of mass and causes the load to teeter on the equipment-formed pinnacle.